If I am not mistaken (and I could very well be), the RAW file is supposed to already include all necessary correction parameters, and CameraRaw processes this info (from lens to body to raw file) automatically?

I'm currently (timidly) working on my PP skills and with the new 3.5 version of Lightroom, you have now a new tab called "lens correction".

This is dedicated to automatically correct distorsion, CA and vignetting of preloaded profile lenses (mostly Nikon and Canon...), but no profile for any m4/3 lenses

I wonder if a non-treated Raw, shooted using EP3/20mm combo for example, bears these corrections. If not, how do you apply "in camera correction" on these defects. If you don't, why ?

Thanks

Click to expand...

Lens profiling on m43 camera/lens combos is done "In camera" due to the inherent heavy distortion correction needed, the theory being that if you can't see how horrid the ACTUAL distortion is, then you won't worry about it.
It is quite common to see lens distortion being handled by the camera firmware on these small lenses, it puts less constraints on the lens designers.
Another factor to consider is that the lens manufacturer has to submit correction details to Adobe to have them incorporated into LR etc or you can profile the lens yourself, there is software readily available.
Considering how good the 20mm is, in camera distortion correction is not something to be too worried about, it certainly doesn't worry me.
The 14mm is much more corrected than the 20mm and the Leica lens variants aren't allowed to have distortion correction applied in camera at all as they feel it would lower their name/reputation for optical quality.